Hydrologic respones to land management and villagers' willingness to pay for improved watwershed management in the Chi River Sub-Basin Northeast Thailand | |
| Author | Yutthaphong Kheereemangkla |
| Call Number | AIT Diss. no.NR-17-04 |
| Subject(s) | Hydrology--Thailand--Chi River Basin Hydrology--Thailand--Chi River watershed Hydrological models--Thailand--Chi River Basin |
| Note | A dissetiation submitted in patiial fulfillment of the requirements for the degree of Doctor of Philosophy in Natural Resources Management, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Series Statement | Dissertation ; no. NR-17-04 |
| Abstract | Land use and land cover change (LULCC) posed significant threats to watershed ecosystem services and human well-being. Loss of forestlands, a serious issue of LULCC, was seen across Thailand. The consequences of watershed degradation caused by LULCC, climate variability, and rapid population growth led to hydrological variations and socioeconomic concerns. These became serious issues in the maintenance of watershed sustainability. The study on the effects of LULCC to hydrologic responses and villagers ' socio-economic information is a major challenge for watershed scientists, managers, and policy makers to ensure watershed sustainability. This is fundamentally important for natural resources utilization, human well-being improvement, and watershed ecosystem restoration. This research was conducted in the no1theast of Thailand. The Chi River Sub-basin covers an area of 10,849. 90 km2 , in which land is predominantly used for agriculture but watershed resources are degraded. A hydrological model that uses the Soil and Water Assessment Tool (SWAT) was adapted with management practices to evaluate hydrologic responses variations. Data from household surveys were gathered to analyze villagers' socio-economic characteristics for better watershed management. The main objective of the research is to assess the effects of LULCC and management practices to watershed functions- water yield and sediment discharge. Additionally, villagers' characteristics and their willingness to pay (WTP) were analyzed, which could serve as significant tools to find suitable approaches. Different changes in land use between 2001 and 2008 were discovered. Field crops and rice paddies decreased, while forestlands, urbanizations, and water bodies increased. When the changes in land use by the modification of various management practices on top of present land use in 2008 were presented, the results showed that the appl ication of agricultural management practice and forest protection measures, land use planning (LUP), and engineered construction measures resulted in a small decrease in discharge and a dramatic decrease in sedimentation compared to the current condition. Conversely, the modification of the Thailand Watershed Classification (WSC) System based on LUP resulted in a significant decrease in discharge and a great increase in sedimentation. Overall, LULCC associated with the conservation practices was clearly identified as a significant source of hydrologic response variations. Appropriate soil and water conservation practices are recommended to sustain this sub-basin. The study on socio-economic characteristics and estimation of villagers' WTP to improve watershed management was conducted using questionnaire surveys, and the division of the sub-basin was based on bio-physio-graphical characteristics into upstream, midstream, and downstream areas. Most respondents gave a positive WTP response. The comparison between WTP and non-WTP respondents for each research site showed that the amount of lands occupied for the non-WTP respondents in the upstream area was higher than for WTP respondents.' In the midstream area, an average age for non-WTP respondents was higher than for WTP respondents and non-WTP respondents earn an average annual income which is significantly lower than the annual income of the WTP respondents. Additionally, the association between the respondents' occupation and their WTP decision in the downstream area was statistically significant. The results discovered that the annual average WTP for upstream, midstream, and downstream areas were US$8.53, US$16.85, and US$11.59 per household, respectively. Therefore, these amounts were approximately 0.29%, 0.89%, and 0.53% of the average annual income of the respondents for each study area respectively. The factors affecting villagers' WTP for improved watershed management were analyzed using the ordinal logistic regression (OLR) model. The results showed that the two variables- occupation (business) and the amount of lands occupied- negatively influence the respondents' WTP, while the total size of occupied lands and the importance score to manage the watershed defined by the respondents positively influence the respondents' WTP. For further understanding of the guidelines for improved watershed management, the assessment of hydro logic responses due to variation in land management practices showed that management practices that adopt resources conservation principles had a strong effect on both discharge and sedimentation. Additionally, socio-economic and WTP study showed that most respondents gave a positive WTP response. Thus, integrated watershed management should consider all conservation practices and socio-economic dimensions that would affect upstream to downstream resources as well as people communities. Hydrological models and socio-economic perspectives were used effectively to assess the consequences of LULCC and management practices for this sub-basin. The research outputs are important to support the implementation of appropriate conservation practices, management approaches, and policies for watershed sustainability. |
| Year | 2017 |
| Corresponding Series Added Entry | Asian Institute of Technology. Dissertation ; no. NR-17-04 |
| Type | Dissertation |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Development and Sustainability (DDS) |
| Academic Program/FoS | Natural Resources Management (NRM) |
| Chairperson(s) | Shrestha, Rajendra Prasad;Shrestha, Sangam; |
| Examination Committee(s) | Jourdain, Damien;Faysse, Nicolas; |
| Scholarship Donor(s) | Kasetsart University, Bangkok, Thailand - AIT Fellowship; |
| Degree | Thesis (Ph.D.) - Asian Institute of Technology, 2017 |